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A304392 Numbers without a digit 1 with digits in nondecreasing order and the product of digits is a power of 6. 0
6, 23, 49, 66, 229, 236, 334, 389, 469, 666, 2233, 2269, 2349, 2366, 2899, 3338, 3346, 3689, 4499, 4669, 6666, 22239, 22336, 22499, 22669, 23334, 23389, 23469, 23666, 26899, 33368, 33449, 33466, 34899, 36689, 44699, 46669, 66666, 88999, 222299, 222333, 222369, 223349 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Applying any of the following to terms in this sequence in any order gives a term from A276038: - Prepend a 1. - Permute digits. - Do nothing.

Subsequence of A276038.

LINKS

Table of n, a(n) for n=1..43.

EXAMPLE

229 is in the sequence because it has digits in nondecreasing order, no digit 1 and a product of digits 2*2*9 = 36 which is a power of 6.

MATHEMATICA

Select[Range[10^6], And[FreeQ[#, 1], AllTrue[Differences@ #, # > -1 &], IntegerQ@ Log[6, Times @@ #]] &@ IntegerDigits@ # &] (* Michael De Vlieger, Jun 30 2018 *)

PROG

(PARI) is(n) = my(d = digits(n), p = prod(i = 1, #d, d[i])); d[1] >= 2 && vecsort(d) == d && 6^logint(p, 6) == p

CROSSREFS

Cf. A009994, A276038.

Sequence in context: A081097 A031293 A250647 * A235332 A026817 A022269

Adjacent sequences:  A304389 A304390 A304391 * A304393 A304394 A304395

KEYWORD

nonn,base

AUTHOR

David A. Corneth, Jun 20 2018

STATUS

approved

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Last modified May 28 17:37 EDT 2020. Contains 334684 sequences. (Running on oeis4.)